Cowpea (Vigna unguiculata (L.) Walp) is a tropical grain legume, which plays an important nutritional role in developing countries of the tropics and subtropics, especially in sub-Saharian Africa, Asia, Central and South America. Its production is limited by a lot of environmental stresses and drought seems to be one of the most important. It has been reported that cowpea has in its genome genes encoding proteins associated with environmental stresses. One of those proteins is a group of proteins called dehydrins. We hypothesized that, as dehydrins have been proposed to protect cellular macromolecules and their expression increase in response to dehydration, it should be used as molecular marker for drought stress tolerance. To test this hypothesis, a fragment of dehydrin was amplified and used for analysis of variability dehydrin gene and cowpea. We used also semi-quantitative RT-PCR (Reverse transcription PCR) to evaluate dehydrin gene expression in plants subjected to water stress. An anti-dehydrin antibody was used to study dehydrin protein accumulation under water stress. Analysis of the dehydrin gene variability revealed a high diversity of this protein family and a high identity to Vigna unguiculata dehydrin presented in database associated to chilling tolerance. Expression of dehydrin was high on the wild ecotypes evidencing more adaptability of this group to water deficit. Western blot analysis revealed an apparent absence of dehydrins in leaves and a presence of a constitutive dehydrin in seeds of unstressed plants.
Análise da expressão e acumulação de DHNs em resposta ao défice hídrico em ecotipos moçambicanos de feijão nhemba (Vigna unguiculata Walp.)
BERNARDI, RODOLFO;
2008-01-01
Abstract
Cowpea (Vigna unguiculata (L.) Walp) is a tropical grain legume, which plays an important nutritional role in developing countries of the tropics and subtropics, especially in sub-Saharian Africa, Asia, Central and South America. Its production is limited by a lot of environmental stresses and drought seems to be one of the most important. It has been reported that cowpea has in its genome genes encoding proteins associated with environmental stresses. One of those proteins is a group of proteins called dehydrins. We hypothesized that, as dehydrins have been proposed to protect cellular macromolecules and their expression increase in response to dehydration, it should be used as molecular marker for drought stress tolerance. To test this hypothesis, a fragment of dehydrin was amplified and used for analysis of variability dehydrin gene and cowpea. We used also semi-quantitative RT-PCR (Reverse transcription PCR) to evaluate dehydrin gene expression in plants subjected to water stress. An anti-dehydrin antibody was used to study dehydrin protein accumulation under water stress. Analysis of the dehydrin gene variability revealed a high diversity of this protein family and a high identity to Vigna unguiculata dehydrin presented in database associated to chilling tolerance. Expression of dehydrin was high on the wild ecotypes evidencing more adaptability of this group to water deficit. Western blot analysis revealed an apparent absence of dehydrins in leaves and a presence of a constitutive dehydrin in seeds of unstressed plants.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
